1. Field of the Invention
The present invention relates to the field of graphics. More particularly, the present invention relates to a system and method for enhancing graphics processing through selected placement of one or more graphics operands in system memory.
2. Art Related to the Invention
For a number of years, personal computers (PCs) have been implemented with a graphics subsystem that is responsible for rendering perspective display views of an object or collection of objects (scene) for display. Normally, a three-dimensional (3D) object is represented as polygons having bitmaps applied to their surfaces. These bitmaps are referred to as "texture maps" because they are used to give a sense of texture to the polygonal objects. By applying texture maps to various polygons within the object, reshaping the polygons and remapping the texture maps to the polygons as the perspective view of the viewer changes, it has become possible to render perspective views of the 3D object approximately in real-time.
Normally, the graphics subsystem includes a graphics controller coupled to both a local frame buffer memory and an input/output (I/O) bus such as a Peripheral Component Interconnect (PCI) bus. To maximize performance, the local frame buffer memory is sized to include operands which are loaded with data to support graphics operations. These graphics operands include a rendering buffer, a Z-buffer, a display buffer(s) and a texture buffer.
In support of these graphics operands, the local frame buffer memory may be implemented with a sufficient memory size to contain each and every texture map possibly used for a scene. However, the amount of memory required by the local frame buffer memory typically would be quite large and too costly to provide. Alternatively, if the texture buffer is implemented with a lesser amount of memory, it may be necessary to constantly reload portions of texture maps to render a 3D object. However, in accordance with conventional system designs having the graphics controller connected to the PCI bus, reloading portions of texture maps greatly reduces the speed of the PC in producing 3D objects for display.
Thus, it would be advantageous to provide a system and method which would allow operands to be placed in main memory without sacrificing system performance.